{"cve":"CVE-2026-49143","nvd":{"published":"2026-06-02T21:16:28.070","modified":"2026-10-08T16:17:18.667","status":"Deferred","description":"BrowserStack Runner through 0.9.5 contains a remote code execution vulnerability in the /_log HTTP handler that allows unauthenticated network-adjacent attackers to execute arbitrary code by submitting crafted JSON request bodies to the handler, which passes user-supplied data to vm.runInNewContext() combined with eval(). Attackers can escape the Node.js vm sandbox by leveraging a host-context Function reference through util.format to access the host process via this.constructor.constructor, achieving full remote code execution on the underlying system without any authentication.","cvss_v4":{"vector":"CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","score":8.7},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":8.8},"cwes":["CWE-94"],"references":["https://github.com/browserstack/browserstack-runner/security/advisories/GHSA-6vr3-7wcx-v5g5","https://www.vulncheck.com/advisories/browserstack-runner-unauthenticated-rce-via-log-http-handler","https://github.com/browserstack/browserstack-runner/security/advisories/GHSA-6vr3-7wcx-v5g5"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:37:48.043517290+00:00"},"epss":{"cve":"CVE-2026-49143","score":0.00802,"percentile":0.5641,"date":"2026-10-26"},"kev":null,"osv":[{"id":"GHSA-6vr3-7wcx-v5g5","url":"https://osv.dev/vulnerability/GHSA-6vr3-7wcx-v5g5","summary":"browserstack-runner vulnerable to Remote Code Execution via vm sandbox escape in _log HTTP handler","modified":"2026-06-03T21:56:25.541425Z","packages":[{"ecosystem":"npm","name":"browserstack-runner","purl":"pkg:npm/browserstack-runner","ranges":["<=0.9.5"],"fixed":[]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}